1. Field of the Invention
The present invention relates to a gene encoding a transcription factor capable of altering characters of a plant and its use. More particularly, the present invention relates to the PetSPL2 gene which is a novel gene derived from Petunia hybrida, genes related thereto, and the use thereof.
2. Description of the Related Art
In order to clarify regulatory mechanisms controlling the characters of a plant, for example, morphogenesis of a flower, molecular biological and molecular geneticical studies have been conducted using Arabidopsis thaliana, Antirrhinum majus, and Petunia hybrida. In particular, Petunia hybrida is preferably used as a subject of studies for the following reasons: high value as a horticultural plant; the presence of various species; ease of transformation; ease to observe due to its large flower; and accumulation of genetical findings (H. Takatsuji, "Molecular mechanism for determining a shape of a plant", Cell Technology, Plant Cell Technology Series (SHUJUNSHA), pp. 96-106).
Genes which cause mutation have been isolated from mutants in which floral organs of the above-mentioned plant is altered. As a result, it is becoming clear that transcription factors play important roles in differentiation and morphogenesis of a flower. For example, SUPERMAN of Arabidopsis thaliana is a transcription factor having a zinc finger motif as a DNA binding domain. It is known that, in SUPERMAN mutant with its gene mutated, number of stamens are remarkably increased, and pistils are defective (THE IDEN, April, 1997 (Vol. 51, No. 4), pp. 34-38).
For understanding the mechanism for the control of characters of a plant, it is important to identify a novel transcription factor which is involved in such control. A gene for a transcription factor which controls morphogenesis of a flower may be introduced into a plant by using gene engineering procedure. It is possible to obtain a plant, using gene introduction, having a flower with novel characters which has not been obtained or is not likely to be obtained by a conventional breeding. It is considered that a plant with such novel characters is horticulturally valuable.